12IP-Aliasing:
3============
45IP-aliases are an obsolete way to manage multiple IP-addresses/masks
6per interface. Newer tools such as iproute2 support multiple
7address/prefixes per interface, but aliases are still supported
8for backwards compatibility.
910An alias is formed by adding a colon and a string when running ifconfig.
11This string is usually numeric, but this is not a must.
1213o Alias creation.
14 Alias creation is done by 'magic' interface naming: eg. to create a
15 200.1.1.1 alias for eth0 ...
1617 # ifconfig eth0:0 200.1.1.1 etc,etc....
18 ~~ -> request alias #0 creation (if not yet exists) for eth0
1920 The corresponding route is also set up by this command.
21 Please note: The route always points to the base interface.
222324o Alias deletion.
25 The alias is removed by shutting the alias down:
2627 # ifconfig eth0:0 down
28 ~~~~~~~~~~ -> will delete alias
293031o Alias (re-)configuring
3233 Aliases are not real devices, but programs should be able to configure and
34 refer to them as usual (ifconfig, route, etc).
353637o Relationship with main device
3839 If the base device is shut down the added aliases will be deleted
40 too.